Acoustic Impedance Tests: Objective tests of middle ear function based on the difficulty (impedance) or ease (admittance) of sound flow through the middle ear. These include static impedance and dynamic impedance (i.e., tympanometry and impedance tests in conjunction with intra-aural muscle reflex elicitation). This term is used also for various components of impedance and admittance (e.g., compliance, conductance, reactance, resistance, susceptance).Acoustics: The branch of physics that deals with sound and sound waves. In medicine it is often applied in procedures in speech and hearing studies. With regard to the environment, it refers to the characteristics of a room, auditorium, theatre, building, etc. that determines the audibility or fidelity of sounds in it. (From Random House Unabridged Dictionary, 2d ed)Transducers: Any device or element which converts an input signal into an output signal of a different form. Examples include the microphone, phonographic pickup, loudspeaker, barometer, photoelectric cell, automobile horn, doorbell, and underwater sound transducer. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Electric Impedance: The resistance to the flow of either alternating or direct electrical current.Ultrasonography: The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.Plethysmography, Impedance: Recording changes in electrical impedance between electrodes placed on opposite sides of a part of the body, as a measure of volume changes in the path of the current. (Stedman, 25th ed)Cardiography, Impedance: A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck and around the lower thorax. It is used principally to calculate stroke volume and cardiac volume, but it is also related to myocardial contractility, thoracic fluid content, and circulation to the extremities.Dielectric Spectroscopy: A technique of measuring the dielectric properties of materials, which vary over a range of frequencies depending on the physical properties of the material. The technique involves measuring, over a range of frequencies, ELECTRICAL IMPEDANCE and phase shift of an electric field as it passes through the material.
(1/154) Confirmation of deafness in infancy.

AIM: To assess delay in confirming hearing impairment in infants identified by universal neonatal screening and to investigate the causes. PATIENTS: Infants identified from 25 199 babies screened from January 1992 to December 1997. METHODS: A two stage transient evoked oto-acoustic emission test (TEOAE), with a threshold auditory brainstem response (ABR) recording undertaken on those who failed. The screen identified infants with a permanent congenital hearing impairment (PCHI) averaging 40 dBnHL or worse in the best ear. Those with less impairment were also ascertained. The positive predictive value (PPV) of the ABR test and measures of delay between identification and eventual diagnosis were analysed. RESULTS: A targeted PCHI was found in 1.18/1000 neonates. The PPV of the ABR for confirming a targeted PCHI was 100% when the ABR threshold was >/= 80 dBnHL. Nine of 11 infants with this threshold had severe or profound permanent deafness. The delay from ABR to audiological certainty was about 1 month-diagnosis was confirmed around 3 months. There was uncertainty when the ABR was 40-80 dBnHL. The PPV was 60% and 8% when the ABR thresholds were 70 dBnHL and 50 dBnHL, respectively. 85 of 111 infants with ABR thresholds in this range had a temporary conductive impairment. Their early diagnosis depended upon the type and degree of hearing impairment and diagnosis was delayed to about 8 months in these infants. CONCLUSIONS: Hearing impairments identified by universal screening are delayed in all but those with severe or profound bilateral PCHI. This delay can be reduced by applying in early infancy a battery of audiological tests and requires further exploration.  (+info)

(2/154) Otolaryngological findings in congenital nasolacrimal duct obstruction and implications for prognosis.

AIM: To investigate otolaryngological abnormalities associated with congenital nasolacrimal duct obstruction (CNLDO) and their effect on the prognosis. METHODS: 65 consecutive cases of CNLDO were followed up with routine otorhinolaryngological examination with tympanometry. RESULTS: Otitis media with effusion (OME) and uvula bifida were detected in 44.6% and 9.2% of the children, respectively. Medical treatment and probing were less effective in patients with OME (p<0. 05). CONCLUSIONS: OME and uvula bifida are significant anomalies associated with CNLDO and the former has a marked effect on the prognosis. This finding may help to determine the patients who will need further treatment after massage and probing.  (+info)

(3/154) Tympanometry for diagnosis and treatment of otitis media in general practice.

OBJECTIVE: The aim of this study was to evaluate the role of tympanometry for diagnosis, treatment and follow-up of otitis media in general practice. METHODS: The results from otoscopy performed by 40 physicians in general practice in Vejle County, Denmark were combined with the clinical condition and this was recorded as the preliminary decision about diagnosis, treatment and follow-up. Subsequently, tympanometry was performed in 3176 children aged between 1 month and 16 years; a total of 6352 tympanometries. With this added knowledge, a final decision about diagnosis, treatment and follow-up was recorded. The practitioners were trained in performing tympanometry including the interpretation of the results. Simultaneously, they were involved in the establishment of guidelines for diagnosis, treatment and follow-up of otitis media in general practice. The main outcome measures were changes between preliminary and final decisions about diagnoses, treatments and follow-up regimens. RESULTS: Tympanometry was performed successfully in 87.7% of the children, and in 26.4% changes in diagnoses were found. However, tympanometry did not influence the distributions of the main outcome measures in the sample as a whole. Uncomplicated cases were checked in general practice and referrals to specialists were not increased. CONCLUSION: Tympanometry can be performed successfully in general practice after appropriate instruction. In 26.4% of children, the diagnoses were changed, which may result in more appropriate treatment and follow-up. Tympanometry is a clinically relevant supplement to the examination of a child in general practice.  (+info)

(4/154) Behaviour and developmental effects of otitis media with effusion into the teens.

OBJECTIVE: To examine whether behavioural or cognitive sequelae of otitis media with effusion (OME) continue into late childhood and the early teens (11-18 years). SETTING: Data from a large multipurpose birth cohort study: the Dunedin multidisciplinary health and development study. PARTICIPANTS: Around 1000 children from the study. The main independent variable of interest was otological status of the child up to age 9. MAIN OUTCOME MEASURES: Parent and teacher rated behaviour problems, including antisocial, neurotic, hyperactive, and inattentive behaviours, and tests of academic achievement including intelligence quotient (IQ), reading, and spelling were available in a high proportion of the cohort at ages 11 to 18 years. RESULTS: After adjustments for covariates such as socioeconomic status, hyperactive and inattentive behaviour problems were evident as late as 15 years, and lower IQ associated with OME remained significant to 13 years. The largest effects were observed for deficits in reading ability between 11 and 18 years. CONCLUSIONS: No previous study considering behaviour problems as an outcome has followed children long enough to determine whether some of the early sequelae of OME are still present in the early to late teens. Some developmental sequelae of OME, particularly deficits in reading ability, can persist into late childhood and the early teens.  (+info)

(5/154) Does early detection of otitis media with effusion prevent delayed language development?

OBJECTIVE: To consider whether earlier detection of otitis media with effusion (OME) in asymptomatic children in the first 4 years of life prevents delayed language development. METHODS: MEDLINE and other databases were searched and relevant references from articles reviewed. Critical appraisal and consensus development were in accordance with the methods of the Canadian Task Force on Preventive Health Care. RESULTS: No randomised controlled trials assessing the overall screening for OME and early intervention to prevent delay in acquiring language were identified, although one trial evaluated treatment in a screened population and found no benefit. The "analytic pathway" approach was therefore used, where evidence is evaluated for individual steps in a screening process. The evidence supporting the use of tools for early detection such as tympanometry, microtympanometry, acoustic reflectometry, and pneumatic otoscopy in the first 4 years of life is unclear. Some treatments (mucolytics, antibiotics, steroids) resulted in the short term resolution of effusions as measured by tympanometry. Ventilation tubes resolved effusions and improved hearing. Ventilation tubes in children with hearing loss associated with OME benefited children in the short term, but after 18 months there was no difference in comparison with those assigned to watchful waiting. Most prospective cohort studies that evaluated the association between OME and language development lacked adequate measurement of exposure or outcome, or suffered from attrition bias. Findings with regard to the association were inconsistent. CONCLUSIONS: There is insufficient evidence to support attempts at early detection of OME in the first 4 years of life in the asymptomatic child to prevent delayed language development.  (+info)

(6/154) Auditory system: Peripheral nonlinearity and central additivity, as revealed in the human stapedius-muscle reflex.

Human stapedius-muscle contractions in response to 3-kHz, 20-msec tone bursts were determined indirectly by measuring the associated acoustic-impedance changes at the tympanic membrane with an acoustic bridge. The measurement was possible because the bridge practically eliminates the effect of the ear-canal air volume interposed between the tympanic membrane and the tip of the measuring tube. By using burst pairs, temporal additivity of the muscle responses was demonstrated both when the stimulus bursts were presented contralaterally to the measured impedance changes and when the first burst was presented ipsilaterally. The summation time constant was on the order of 200 msec, much longer than the twitch time constant of the muscle fibers. Therefore, the summation had to take place in a nucleus preceding the stapedius muscle. The magnitude of the muscle response obeyed a compressive function paralleling the loudness function up to sound pressure levels of at least 120 dB.  (+info)

(7/154) Practical screening priorities for hearing impairment among children in developing countries.

Routine screening for hearing impairment in childhood is now widespread in industrial countries, although there is considerable controversy over the most efficient techniques and procedures. In most developing countries, however, routine screening programmes for hearing impairment do not currently exist. The problems involved in implementing screening programmes in developing and industrial countries are very different, and in selecting screening procedures for a particular population the following factors have to be taken into consideration: the environmental test conditions; the availability of resources for equipment and the training of testers; the local attitudes towards disability; the level of hearing impairment that may cause handicaps; and the major types of pathology causing hearing impairment. We suggest that in developing countries children should be screened at school entry using a simple field audiometer and that the external ear be inspected for the presence of a discharge. There is an urgent need to develop reliable and simple screening procedures for infants and young children; where possible, all children should be screened for severe or significant hearing impairment before the age of 2 years. No screening should, however, be implemented until appropriate follow-up services are available.  (+info)

(8/154) Impedance analysis of the organ of corti with magnetically actuated probes.

An innovative method is presented to measure the mechanical driving point impedance of biological structures up to at least 40 kHz. The technique employs an atomic force cantilever with a ferromagnetic coating and an external magnetic field to apply a calibrated force to the cantilever. Measurement of the resulting cantilever velocity using a laser Doppler vibrometer yields the impedance. A key feature of the method is that it permits measurements for biological tissue in physiological solutions. The method was applied to measure the point impedance of the organ of Corti in situ, to elucidate the biophysical basis of cochlear amplification. The basilar membrane was mechanically clamped at its tympanic surface and the measurements conducted at different radial positions on the reticular lamina. The tectorial membrane was removed. The impedance was described by a generalized Voigt-Kelvin viscoelastic model, in which the stiffness was real-valued and independent of frequency, but the viscosity was complex-valued with positive real part, which was dependent on frequency and negative imaginary part, which was independent of frequency. There was no evidence for an inertial component. The magnitude of the impedance was greatest at the tunnel of Corti, and decreased monotonically in each of the radial directions. In the absence of inertia, the mechanical load on the outer hair cells causes their electromotile displacement responses to be reduced by only 10-fold over the entire range of auditory frequencies.  (+info)

*  List of MeSH codes (E01)
... hearing tests MeSH E01.370.382.375.050 --- acoustic impedance tests MeSH E01.370.382.375.060 --- audiometry MeSH E01.370. ... impedance MeSH E01.370.370.610.610.200 --- cardiography, impedance MeSH E01.370.370.750 --- tilt-table test MeSH E01.370. ... intradermal tests MeSH E01.370.750.300.400 --- kveim test MeSH E01.370.750.300.750 --- skin test end-point titration MeSH ... intradermal tests MeSH E01.450.495.750.300.540 --- kveim test MeSH E01.450.495.750.300.750 --- skin test end-point titration ...
*  Infrasound
... is made of a material having a low acoustic impedance and has a sufficiently thick wall to ensure structural stability. Close- ... In the proposed test, test parameters will be sensitivity, background noise, signal fidelity (harmonic distortion), and ... In music, acoustic waveguide methods, such as a large pipe organ or, for reproduction, exotic loudspeaker designs such as ... In the second concert, the pieces that were to carry a 17 Hz undertone were swapped so that test results would not focus on any ...
*  Western concert flute
Acoustic impedance of the embouchure hole appears the most critical parameter. Critical variables affecting this acoustic ... Tests with experienced professional flutists and listeners and one model of a flute made by Muramatsu from 7 different ... "Acoustic impedance of the flute". Flute acoustics: an introduction. "Curved Head Student Flute by Gear4music". Gear4music. 2016 ... However, small deviations from the objective 'mechanical' pitch (which is related to acoustic impedance of a given fingering) ...
*  Bomb suit
It was found that a layer with high acoustic impedance with a backing of a softer, low acoustic impedance layer (such as low ... Bass et al., 2006, Comparative testing of effectiveness of different helmet/shield designs at reducing head acceleration due to ... similar to the NIJ standards that are widely used to test and compare body armor or materials used to stop ballistic threats. ... it was also shown that it is important to understand the frequency content of the applied blast wave and to experimentally test ...
*  Brüel & Kjær
... noise and vibration testing and structural dynamics testing. Brüel & Kjær offers products that cover a wide range of acoustic ... and acoustic panel in-situ impedance measurement) Brüel & Kjær also supplies in-flight engine monitoring with flight-certified ... Other systems have tested Astrium's satellite prior to launch, and performed qualification and acceptance testing, such as the ... These ensure the quality of new lighter material applications by modal testing and improving the quality and test efficiency in ...
*  Seismic inversion
CSSI transforms seismic data to a pseudo-acoustic impedance log at every trace. Acoustic impedance is used to produce more ... which can then be narrowed through testing for best fit against various measurements (including production data). An example of ... The inversion results in acoustic impedance (AI), which is the product of rock density and p-wave velocity. Unlike seismic ... A good (CSSI) algorithm will produce four high-quality acoustic impedance volumes from full or post-stack seismic data: full- ...
*  Non-contact ultrasound
... the use of some type of acoustic coupling medium in order to efficiently transmit the energy from the sensor to the test ... piezoelectric transducer can produce frequencies in the MHz that can easily propagate through even high acoustic impedance ... Non-contact ultrasound (NCU) is a method of non-destructive testing where ultrasound is generated and used to test materials ... However in non-contact ultrasound, ambient air is the only acoustic coupling medium. An electromagnetic acoustic transducer ( ...
*  Acoustic liner
Moreover, the acoustic performance is linked to the acoustic impedance which can be measured with one of the following ... The acoustic liners' performance can be verified in dedicated experimental test rigs, by means of virtual prototypes or by ... Effects of liner geometry on acoustic impedance. AIAA Paper, 2446, 2002. Dean, P. D.,An In-Situ Method of Wall Acoustic ... Moreover, the in-situ method is the only one able to measure the impedance directly on full scale acoustic liners. Murray, P., ...
*  Acoustic reflex
Most of the time, the stapedius reflex is tested with tympanometry. The contraction of the stapedius muscle stiffens the middle ... 267-9. ISBN 0-07-285293-3. "Impedance Audiometry". MedScape. W. Niemeyer (1971). "Relations between the Discomfort Level and ... the sound used to trigger the acoustic reflex). For most animals, the acoustic reflex is the contraction of both middle ear ... The acoustic reflex threshold (ART) is the sound pressure level (SPL) from which a sound stimulus with a given frequency will ...
*  Acoustic metamaterial
First successful industrial applications of acoustic metamaterials are tested for aircraft insulations. Since the acoustic ... Based on Newton's observation we can conclude that a key factor for acoustic band-gap engineering is impedance mismatch between ... High-resolution acoustic imaging techniques are the essential tools for nondestructive testing and medical screening. However, ... We can exploit this concept with periodic (and handcrafted) arrangements of impedance mismatched elements to affect acoustic ...
*  Acoustic rhinometry
The test is carried out by generating an acoustic pulse from a speaker or spark source and this sound pulse is transmitted to ... is reflected back to a microphone and this reflection is generated according to the changes in the local acoustic impedance ... Acoustic Rhinometry is a diagnostic measurement of the nose and the nasal cavity through acoustic reflections. It can be used ... O, Hilberg; AC, Jackson; DL, Swift; OF, Pedersen (1989). "Acoustic Rhinomtry: Evaluation of nasal cavity geometry by acoustic ...
*  Project Artemis
TEST OF PROJECT ARTEMIS ACOUSTIC SOURCE PROJECT ARTEMIS ACOUSTIC SOURCE - ACOUSTIC TEST PROCEDURE Project ARTEMIS High Power ... Analysis of Transducer-Impedance Variations on the Amplifier Operation. Project ARTEMIS High-Power Acoustic Source. PROJECT ... High Power Acoustic Source. Interim Report on Acoustic Performance Project ARTEMIS. High Power Acoustic Source. Interim Report ... High Power Acoustic Source. PROJECT ARTEMIS ACOUSTIC SOURCE SUMMARY REPORT High-Data-Rate System for the ARTEMIS Long-Range ...
*  Pennsylvania State University Applied Research Laboratory
The Acoustic Test Tank is equipped with the instrumentation required for determining the acoustic characteristics of sonar ... devices designed for frequency response calibrations, radiation pattern plots, and impedance and admittance characterizations. ... Laboratory which houses an array of tanks including an Acoustic Reverberant Tank and an Acoustic Test Tank for acoustic ... ARL operates the Advanced Nuclear Fuel Test Facility (ANFTF) which is a Westinghouse-funded facility to test advanced power ...
*  Voice over IP
Common causes of echo include impedance mismatches in analog circuitry and acoustic coupling of the transmit and receive signal ... "Performance and Stress Testing of SIP Servers, Clients and IP Networks". StarTrinity. 2016-08-13. "Testing Voice over IP (VolP ... The metrics are determined by VoIP performance testing and monitoring. A VoIP media gateway controller (aka Class 5 Softswitch ... "Methodology for SIP Infrastructure Performance Testing" (PDF). Miroslav Voznak, Jan Rozhon. 2016-08-14. "Voice over IP (VoIP) ...
*  Sonic weapon
... which reflect the sound due to mismatched acoustic impedance. Brown note Sone (a unit of loudness of sound) Sound pressure ... Tests performed on mice show the threshold for both lung and liver damage occurs at about 184 dB. Damage increases rapidly as ... A long-range acoustic device has been used by the crew of the cruise ship Seabourn Spirit to deter pirates who chased and ... A similar system is called a "magnetic acoustic device." 'Mobile' sonic devices have been used in the United Kingdom to deter ...
*  Reflection seismology
The acoustic (or seismic) impedance, Z, is defined by the equation: Z = V ρ {\displaystyle Z=V\rho \ } , where V is the seismic ... This led to another variation on the NATS survey type, the wide-azimuth towed streamer (or WAZ or WATS) and was first tested on ... Hydrocarbon exploration - used by the hydrocarbon industry to provide a high resolution map of acoustic impedance contrasts at ... Seismic waves are mechanical perturbations that travel in the Earth at a speed governed by the acoustic impedance of the medium ...
*  Dynaco
These boards were wired at the factory, tested and packaged with the unassembled chassis. It remained only for the consumer to ... The resistant venting action lowered the "Q" of the system and reduced impedance variation near resonance in the A-Series ... whose acoustic resistance is very carefully controlled. ... tested circuit boards that only required the customer to wire ... which generally required the purchaser to assemble and test the PC boards themselves, a relatively precise and time-consuming ...
*  Measurement microphone calibration
... allowing the acoustic transfer impedance Z a c {\displaystyle Z_{ac}} to be easily modelled. One of the microphones is then ... This service is offered by some microphone manufacturers and by independent testing laboratories. Microphone calibration by ... and the acoustical transfer impedance equals the electrical transfer impedance. Z i j = U j I i = M i Z a c M j {\displaystyle ... is determined during the calibration procedure by measuring the current and voltage and the acoustic transfer impedance depends ...
*  Reverberation room
Anechoic Chamber: another acoustic test facility Echo chamber: a reverberation room used for music recording Electromagnetic ... The change of impedance (compared to the air) these surfaces present to incident sound is so large that virtually all of the ... an electromagnetic environment mainly for Electromagnetic Compatibility testing ISO Standard for Measurement of Acoustic ... additional acoustic diffusers are often used to create more reflecting surfaces and further encourage even distribution of any ...
*  Dynamic angiothermography
However, due to the general equality in acoustic impedance for many types of structures in the breast ultrasound imaging ... DATG is not a test that directly substitutes for other tests, but stands in relation to them as a technique that provides a ... The angiothermography is not a test that substitutes for other tests, but stands in relation to them as a technique that gives ... As such, it has been most successfully employed in combination with other tests to improve the quality of the diagnosis. ...
*  Horn analyzer
In an acoustic set, the parts act like narrow pass-band filters, and their central frequencies should be perfectly aligned to ... Impedance analyzers can be used as advanced horn analyzers, but are not usually a cost-effective alternative for everyday ... A digital horn analyzer performs a frequency sweep while monitoring the current flowing through the device under test, in order ... The anti-resonance is the frequency at which the current encounters maximum impedance, and the resonance is the frequency of ...
*  Reservoir modeling
Acoustic impedance varies by rock type and can therefore be correlated to rock properties using rock physics relationships ... These blind-well mode inversions test the reliability of the constrained inversion and remove potential biased. This ... Seismic surveys measure acoustic impedance contrasts between rock layers. As different geologic structures are encountered, the ... Geostatistical inversion simultaneously inverts for impedance and discrete properties types, and other petrophysical properties ...
*  Synthetic seismogram
This acoustic impedance log is combined with the velocity data to generate a reflection coefficient series in time. This series ... It can also be used either to test possible interpretation models for 2D and 3D seismic data or to model the response of the ... This information is then used to calculate the variation in acoustic impedance down the well bore using the Zoeppritz equations ... It may also be used to test out different geometries of structures such as salt diapirs, to see which gives the best match to ...
*  Echo suppression and cancellation
Echoes in this case did not include long echoes caused by acoustic coupling, but did include short echoes caused by impedance ... ITU standards G.168 and P.340 describe requirements and tests for echo cancellers in digital and PSTN applications, ... These methods are commonly called acoustic echo suppression (AES) and acoustic echo cancellation (AEC), and more rarely line ... impedance mismatches, electrical reflections, etc., which varies much less than acoustic echo). In practice, however, the same ...
*  Index of physics articles (A)
Acoustic emission Acoustic holography Acoustic impedance Acoustic interferometer Acoustic levitation Acoustic location Acoustic ... Ammonium uranyl carbonate Amorphous ice Amorphous metal Amorphous solid Amory Lovins Amos Ori Amos de-Shalit Amott test Amount ... lubrication Acoustic metamaterials Acoustic metric Acoustic microscopy Acoustic mirror Acoustic network Acoustic ohm Acoustic ... Acoustic analogy Acoustic approximation Acoustic attenuation Acoustic cleaning Acoustic cloak Acoustic contrast factor Acoustic ...
*  Sound power
... of Acoustic Quantities Associated with a Plane Progressive Acoustic Sound Wave NIOSH Powertools Database Sound Power Testing. ... where z0 is the characteristic specific acoustic impedance. Consequently, I = p v = p 2 z 0 , {\displaystyle I=pv={\frac {p^{2 ... The test environment can be located indoors or outdoors. The ideal environment is on the ground in a large open space or hemi- ... Sound power or acoustic power is the rate at which sound energy is emitted, reflected, transmitted or received, per unit time. ...
Acta Acustica united with Acustica: Ingenta Connect Table Of Contents  Acta Acustica united with Acustica: Ingenta Connect Table Of Contents
A Comparative Study of Impedance and Acoustic Vowel Phonation Signals for Intelligent Voice Quality Assessment of Patients ... Musically Representative Test Signals for Interaural Cross-Correlation Coefficient Measurement pp. 787-796(10) Authors: Neher, ... acoustic materials, acoustic signal processing, computational and numerical acoustics, hearing, audiology and psychoacoustics, ... Calculation of the Acoustic Nonlinearity Parameter B/A for Linear Alkanes by the Lee-Kesler Correlation pp. 756-764(9) Authors: ...
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Wide Frequency Band Test of Hearing in Veterans - Full Text View -  Wide Frequency Band Test of Hearing in Veterans - Full Text View -
Acoustic impedance tests. Additional relevant MeSH terms: Hearing Loss. Deafness. Otitis Media. Otitis Media with Effusion. ... tests of absorbance for improved sensitivity in the assessment of middle-ear function including acoustic reflex testing. The ... Middle ear test [ Time Frame: Assessed at time of enrollment ]. The standard clinical middle ear test, 226 Hz tympanometry, and ... Wideband otoacoustic emission test [ Time Frame: Assessed at time of enrollment ]. An otoacoustic emission test assessed using ...
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Avaliação audiológica, eletroacústica e eletrofisiológica da audição em adultos com...  Avaliação audiológica, eletroacústica e eletrofisiológica da audição em adultos com...
Acoustic impedance tests. Acquired immunodeficiency syndrome. Audiometry. Auditory evoked potentials. Brainstem auditory evoked ... acoustic reflexes, otoacoustic emissions, otoacoustic emissions suppression, and brainstem auditory evoked potential; it was ...
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Persistent alternobaric vertigo at ground level.  Persistent alternobaric vertigo at ground level.
Acoustic Impedance Tests. Adolescent. Diagnosis, Differential. Ear, Middle / physiopathology. Eustachian Tube / physiopathology ...
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Clinical manifestations of aural fullness.  Clinical manifestations of aural fullness.
Acoustic Impedance Tests. Adult. Audiometry, Pure-Tone. Female. Hearing Disorders / diagnosis*, etiology*, physiopathology. ... Audiologic test Audiological tests included otoscopic examinations, pure tone audiometry (PTA), impedance audiometry (IA), ... Among patients who complained of hearing fullness, tests and measures such as impedance audiometry, speech reception threshold ... Physical examination should include the Valsalva test; nasal examinations should include endoscopy; and audiological tests ...
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Allied Health Professions (AHP) & Healthcare Science | Derby Teaching Hospitals NHS Foundation Trust  Allied Health Professions (AHP) & Healthcare Science | Derby Teaching Hospitals NHS Foundation Trust
Acoustic impedance testing including tympanometry and acoustic reflexes. · Speech Audiometry. · Evoked auditory assessment ... Balance Assessment including VNG, caloric and sway testing. · Rehabilitation of hearing loss including the fitting and ... The student's will develop their testing techniques within Orthoptics as well as having an overview of a working Hospital Eye ...
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Allied Health Professions (AHP) & Healthcare Science | Derby Teaching Hospitals NHS Foundation Trust  Allied Health Professions (AHP) & Healthcare Science | Derby Teaching Hospitals NHS Foundation Trust
Acoustic impedance testing including tympanometry and acoustic reflexes. · Speech Audiometry. · Evoked auditory assessment ... Balance Assessment including VNG, caloric and sway testing. · Rehabilitation of hearing loss including the fitting and ... The student's will develop their testing techniques within Orthoptics as well as having an overview of a working Hospital Eye ...
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Refresher Courses Spring 2019  Refresher Courses Spring 2019
Unit II: Ultrasonic testing - includes acoustic impedance and reflection coefficient; refraction and mode conversion; sound ... Level III Study Guide: Visual and Optical Testing (Product Number 2263). *NDT Handbook, 3rd Edition, Vol. 9, Visual Testing ( ... Nondestructive Testing Handbook, Fourth Edition: Volume 1, Liquid Penetrant Testing (Product Number 0142) ... Nondestructive Testing Handbook, Second Edition: Volume 6, Magnetic Particle Testing (Product Number 0148) ...
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Timothy Hullar - Publications
     - Oregon Health & Science University  Timothy Hullar - Publications - Oregon Health & Science University
Vascular pulsations on impedance audiometry as a sign of a third-mobile window lesion. Hullar, T., Jun 2010, In : Otology and ... Acoustic Impedance Tests 37 Citations (Scopus) Phenotypic characteristics of early Wolfram syndrome. Marshall, B. A., ...
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Assessing Sensorineural Hearing Loss Using Various Transient-Evoked Otoacoustic Emission Stimulus Conditions<...  Assessing Sensorineural Hearing Loss Using Various Transient-Evoked Otoacoustic Emission Stimulus Conditions<...
Clinical audiometry, immittance, and an experimental wideband test battery, which included reflectance and TEOAE tests ... keywords = "Sensorineural hearing loss, Transient-evoked otoacoustic emissions, Wideband acoustic immittance",. author = " ... Clinical audiometry, immittance, and an experimental wideband test battery, which included reflectance and TEOAE tests ... Clinical audiometry, immittance, and an experimental wideband test battery, which included reflectance and TEOAE tests ...
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Sreedharan, S. S.<...  Sreedharan, S. S.<...
Acoustic Impedance Tests Cochlea Staging of laryngeal and hypopharyngeal cancer: Computed tomography versus histopathology. ...
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Michael Hunter - Research Output
     - the UWA Profiles and Research Repository  Michael Hunter - Research Output - the UWA Profiles and Research Repository
Acoustic Impedance Tests 55 Citations (Scopus) Respiratory symptoms and illness in older Australians: The Burden of obstructive ...
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Search Articles | University of Toronto Libraries  Search Articles | University of Toronto Libraries
acoustic impedance tests (1) 1 Cancel. Any. index medicus (19) otorhinolaryngology (15) ... Genetic Testing , Humans , Japan , Asian Continental Ancestry Group - genetics , Infant , Male , Hearing Loss, Sensorineural - ... Predictive Value of Tests , Endoscopes , Otolaryngology - instrumentation , Humans , Oropharynx - pathology , Endoscopy - ...
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Search Articles | University of Toronto Libraries  Search Articles | University of Toronto Libraries
Acoustic Stimulation , Humans , Middle Aged , Perceptual Distortion - physiology , Acoustic Impedance Tests , Case-Control ... Retrocochlear hearing loss , Distortion-product otoacoustic emission tests , Acoustic neuroma , Nerve origin , acoustic neuroma ... Hearing Tests , Infant, Newborn , Acoustic emission testing , Infants (Newborn) , Analysis ... 5. Full Text Association between mode of delivery and failure of neonatal acoustic emission test: A retrospective analysis ...
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Ultrasound Velocity Measurement in a Liquid Metal Electrode | Protocol  Ultrasound Velocity Measurement in a Liquid Metal Electrode | Protocol
Maximum acoustic power is transmitted when the acoustic impedance of the transducer material and the test fluid are identical; ... which separate the delicate electro-acoustic components from the test fluid with an acoustic waveguide, have been demonstrated ... Though direct contact between the ultrasound transducer and the test fluid yields strong signals, careful acoustic design might ... A wall between the transducer and test fluid might also be treated or conditioned to reduce the adverse effects of oxide in the ...
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Acoustic impedance | definition of acoustic impedance by Medical dictionary  Acoustic impedance | definition of acoustic impedance by Medical dictionary
... acoustic impedance explanation free. What is acoustic impedance? Meaning of acoustic impedance medical term. What does acoustic ... Looking for online definition of acoustic impedance in the Medical Dictionary? ... The acoustic impedance of bone may be nearly five times as great as that of blood. Testing middle ear acoustic impedance is ... acoustic impedance at normal incidence of fluids, acoustic impedance at oblique incidence in fluids, the Biot theory of sound ...
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Brazilian Journal of Otorhinolaryngology  Brazilian Journal of Otorhinolaryngology
Middle ear, Down syndrome, Acoustic impedance tests. Palavras-chave. Orelha média, Sindrome de Down, Testes de impedância ... Sound-conduction effects on DPOAE screening outcomes in newborn infants: test performance of wideband acoustic transfer ... the percentage chart of acoustic absorbance was observed during the test performance, on the Titan equipment screen; however, ... 3 recommend audiological tests at birth, and monitoring every 6 months up to the age of 3 years, with annual tests after 3 ...
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Brazilian Journal of Otorhinolaryngology  Brazilian Journal of Otorhinolaryngology
Middle ear, Down syndrome, Acoustic impedance tests. Palavras-chave. Orelha média, Sindrome de Down, Testes de impedância ... Sound-conduction effects on DPOAE screening outcomes in newborn infants: test performance of wideband acoustic transfer ... the percentage chart of acoustic absorbance was observed during the test performance, on the Titan equipment screen; however, ... 3 recommend audiological tests at birth, and monitoring every 6 months up to the age of 3 years, with annual tests after 3 ...
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Clinical and Genetic Testing of Patients With Usher Syndrome - Full Text View -  Clinical and Genetic Testing of Patients With Usher Syndrome - Full Text View -
Measured by acoustic impedance measurement. *Changes in vestibular functions [ Time Frame: Up to 4 weeks ]. Measured by ... Clinical and Genetic Testing of Patients With Usher Syndrome. The safety and scientific validity of this study is the ... MedlinePlus related topics: Genetic Testing Usher Syndrome Genetic and Rare Diseases Information Center resources: Retinitis ... Measured by electronic audiometry (ASSR test). *Changes in efficient sound transmission in the middle ear [ Time Frame: Up to 4 ...
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  • What Is Nondestructive Testing? (
  • It should be noted that while the medical field uses many of the same processes, the term "nondestructive testing" is generally not used to describe medical applications. (
  • The final report presents the results of an experimental and computational study on the recently-developed air-coupled impact-echo (IE) nondestructive testing (NDT) method, in which microphones replace the traditional physically-coupled IE sensors. (
  • Double-evoked TEOAEs were measured using a chirp stimulus, in which the stimuli had an extended frequency range compared to clinical tests. (
  • The provision of guidance in ventilator therapy by continuous monitoring of regional lung ventilation, aeration and respiratory system mechanics is the main clinical benefit of electrical impedance to. (
  • For visitors who are not already familiar with NDT, the general information below is intended to provide a basic description of NDT and the most common test methods and techniques used when performing NDT. (
  • Also, standards covering these test methods are listed on the "Codes and Standards Bodies" page under the NDT Resources Center tab. (
  • Each of these test methods will be described here, followed by the other, less often used test methods. (
  • Two-dimensional (2D) IE scanning tests were conducted on the bridge deck with artificial defects to locate the defect positions by the air-coupled and physically coupled test methods. (
  • Results obtained by these two methods are in good agreement, demonstrating the accuracy and feasibility of the air-coupled IE test method. (
  • In music, acoustic waveguide methods, such as a large pipe organ or, for reproduction, exotic loudspeaker designs such as transmission line, rotary woofer, or traditional subwoofer designs can produce low-frequency sounds, including near-infrasound. (
  • The objective of this study was to compare TEOAEs from 0.79 to 8 kHz using these three stimulus conditions in adults to assess test performance in classifying ears as having either normal hearing or SNHL. (
  • The accuracy and feasibility of the air-coupled test method to determine the solid thickness of concrete structures and to detect defects or flaws, such as delaminations or voids, were verified by comparing test results obtained via the air-coupled and physically-coupled sensors. (
  • The goal of this feasibility study is to evaluate the ability of Electrical Impedance Tomography (EIT) for providing regional and quantitative information about the extent and nature of br. (
  • Conclusions: TEOAEs evaluated in an ambient condition, at TPP and in a power-weighted stimulus condition, had good test performance in identifying ears with SNHL based on SNR and CSM in the frequency range from 1 to 8 kHz and showed good test-retest reliability. (
  • Medical equipment is often rated according to impedance to allow for optimum performance by matching impedance ratings. (
  • To develop an optimum testing system and verify the new method, two concrete plates were tested in the laboratory, one of which was a solid concrete slab, and the other was a mock-up reinforced concrete bridge deck with artificial defects. (
  • Finite element method (FEM) based numerical simulations were conducted using COMSOL Multi-physics software to understand the mechanics of the air-coupled IE test, determine the optimum geometry for the parabolic reflector, and investigate the effects of the microphone height. (
  • Types of testing conducted in the ATF include Transmission Loss, Sound Power, and Vibration testing. (
  • The area under the receiver operating characteristic curve (AUC) was measured at audiometric frequencies between 1 and 8 kHz to determine TEOAE test performance in distinguishing SNHL from normal hearing. (
  • A transformer can be used between components to cause the impedances of unequal systems to match. (
  • In contrast to NDT, other tests are destructive in nature and are therefore done on a limited number of samples ("lot sampling"), rather than on the materials, components or assemblies actually being put into service. (
  • A novel method for the imaging of static scenes using Electrical Impedance Tomography (EIT) is reported with implementation and validation using numerical and phantom models. (
  • The main difference between ASSR and ABR is that ASSR is usually faster to show that hearing is normal because both ears can be tested at the same time, whereas with ABR, each ear must be tested one at a time. (
  • A test that uses sounds at different volumes and pitches with headphones over your child's ears. (
  • Mean test-retest reliability of TEOAE SNR was ≤4.3 dB for both hearing groups across all frequencies, although it was generally less (≤3.5 dB) for lower frequencies (1 to 4 kHz). (
  • Global hearing screening and diagnostic devices market has been segmented on the basis of product, indications, and test. (
  • Your child's audiologist will take a complete hearing history to help evaluate your child's hearing, There are many different types of hearing tests that can be used to check your child's hearing. (
  • Most audiologists will use several different tests to get a complete picture of your child's hearing. (
  • A hearing test that uses small disk-like sensors attached with adhesive to the baby's scalp. (
  • This hearing test is typically done for infants over six months of age. (
  • This test does not show whether the hearing is normal. (
  • This is a sleeping hearing test. (
  • For this test, small disk-shaped sensors are placed behind each ear and on your baby's forehead. (
  • Imaging fast electrical activity in the brain during ictal epileptiform discharges with electrical impedance tomography. (
  • The purpose of this study is to detect vesicoureteral reflux (VUR) non-invasively using electrical impedance tomography (EIT). (
  • Regional pulmonary effects of bronchoalveolar lavage procedure determined by electrical impedance tomography. (
  • Three-dimensional Electrical Impedance Tomography With Multiplicative Regularization. (
  • The multiplicative regularization scheme is applied to three-dimensional electrical impedance tomography (EIT) image reconstruction problem to alleviate its ill-posedness. (
  • Today modern nondestructive tests are used in manufacturing, fabrication and in-service inspections to ensure product integrity and reliability, to control manufacturing processes, lower production costs and to maintain a uniform quality level. (
  • A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck and around the lower thorax. (